Notes. 
309 
albumin. The object of the drying-tubes is to prevent any more 
moisture than is already present in its substance reaching the albumin 
from the steam or from any other source. Thus heated, the albumin 
is found to have become insoluble in water, and in fact to have under¬ 
gone a change corresponding to coagulation. 
If, however, the albumin be carefully dried before being subjected 
to these conditions, the results are quite different 1 . For the present 
purpose it was found to be sufficient to expose a thin layer of albumin 
in a glass dish to a temperature of 52-55 0 C. in an incubator. This 
ensures a very thorough desiccation. The process may be hastened by 
introducing a vessel of sulphuric acid, though this precaution was not 
found to be necessary. Thus dried, the albumin loses its shellac or 
glue-like appearance, and easily crumbles to very small particles. 
On comparing the solubility and coagulability of this specially dried 
material with the ordinary sample, no difference could be detected in 
any respect. 
Numerous experiments were made with this dried material, of 
which the following may be taken as typical. It may be added that 
the results throughout were almost surprisingly uniform in the different 
experiments made. 
A sample of the specially dried albumin was introduced in a flask 
so as to form a thin layer over the bottom. The flask was connected 
with drying-tubes filled with calcium chloride, and with phosphorus 
pentoxide. The flask was warmed and cooled rapidly several times, 
in order to cause the contained air to circulate through the drying- 
tubes. 
The temperature of the flask was then raised in a brine bath to 
102 0 C., and kept at this temperature during the whole of one day 
(six hours). Next day, and without opening or disturbing the appa¬ 
ratus, the temperature was again raised to io7°C., and finally to 
1 io° C. It was maintained between these limits for seven hours; thus 
the contents of the flask had been for thirteen hours exposed to a 
temperature of considerably over ioo°C. 
On testing the albumin it was found to be soluble in water, and in 
no way, as far as could be observed, did it differ from the unheated 
material. On gradually warming the solution side by side with a 
1 Lehmann incidentally observed that albumin dried in vacuo could be heated 
to ioo°C. without its power of solution and subsequent coagulation being thereby 
impaired. 
Y 2 
